# Math Common

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Math conventions to reduce boilerplate code.

## Installation

Add Math Common to your Gradle build script:

```kotlin
repositories {
    mavenCentral()
}

dependencies {
    implementation("com.eriksencosta.math:common:0.3.0")
}
```

If you're using Maven, add to your POM xml file:

```xml
<dependency>
    <groupId>com.eriksencosta.math</groupId>
    <artifactId>common</artifactId>
    <version>0.3.0</version>
</dependency>
```

## Usage

### Rounding

The library provides the `Rounding` [strategy](https://refactoring.guru/design-patterns/strategy) to make rounding
easier:

```kotlin
1.25.round(1) // 1.3
```

By default, the [RoundingMode.HALF_EVEN](https://docs.oracle.com/javase/8/docs/api/java/math/RoundingMode.html#HALF_EVEN) is
used for rounding (it is the rounding logic commonly taught at school). If you want to use a different mode, create a
`Rounding` and use it:

```kotlin
import java.math.RoundingMode

val rounding = Rounding.to(2, RoundingMode.FLOOR)

rounding.round(1.257) // 1.25
rounding.round(1.253) // 1.25

// Alternatively:

1.257.round(rounding) // 1.25
1.253.round(rounding) // 1.25
```

If you want to round the result of a calculation, use the overloaded `round()` method which accepts a function as
parameter:

```kotlin
Rounding.to(2).round { 3.14159 * 10.0.squared() } // 314.16
```

Alternatively:

```kotlin
{ 3.14159 * 10.0.squared() }.round(2) // 314.16
```

### Exponentiation

The extension functions `squared` and `cubed` are available for `BigDecimal`, `Double`, `Float`, `Long`, and `Int`:

```kotlin
2.squared() // 4
2.0.cubed() // 8.0
```

## API documentation

Read the [API documentation](https://blog.eriksen.com.br/opensource/math-common/) for further details.

## License

[The Apache Software License, Version 2.0](https://choosealicense.com/licenses/apache/)